Does your bike VIBRATE?

I have an 85 XJ700 maxim. At 5000 rpm my mirrors become useless. Is this normal?
The original bars were replaced before I bought the bike would bar end weights help?

My hands are numb after the 25 min commute to work. I have large foam grips are there better choices?

 

I have some vibration at 50 - 53 mph, and only at that speed. I don't understand why it would do that then and not at other times. My bike runs best at 70 mph. The vibration is more like a humming and if I gun it, and shoot past the 50 to 53 I don't even notice it. :?:

 

My fingers are pretty numb after any riding at all, but then they're numb after driving an old car any distance at all. I just don't seem to have the best circulation in my hands for some reason. So I'm hoping someone pops into this thread with some really great vibration-damping advice...

 

Ya walk. :lol: :lol: No can't do that either because of the shock on the feet. I just don't know, okay? 8)

 

hmmm my mirrors viberate sometimes. i havent really paid attention to when. Doesnt seem to be too often... ofcourse... i dont usually go 50, its either 25 or 80 (i live in boston... what do you expect?)

 

Front tire balance? I had a balance weight fall off once, and it caused a lot of vibration. But if it's just engine vibration, I think you might be out of luck. Gloves do help a bit, though.

 

A vibration damper such as RTV filling the handlebars or getting a hold of those rubber dampers used in bicycle handlebars might be in order.

 

http://www.barsnake.com/

Rubber handlebar insert. Good reviews.

 

Wow: I have never heared of anyone complaining of a lot of vibration on Any XJ? This being that they are normaly pretty darn smooth running machine. Maybe there is something wrong here? I would like to know more about the bike? Although I know my right hand would become useless after a 15 minutes ride or more untill I had carpultunal surgery.
But that doesn't explane the mirrors.

 

Ya, I can't see anything in my mirrors on the freeway. But I figure if I'm going faster than everyone else, why would I need to look behind me?

 

Good point Blue, the vibration could have origins in another area. This could be an indicator of a more serious problem, I'd take note!

 

Almost every motorcycle should have rpms where they become buzzy - this is an unfortunate side affect of having a lot of mass rotating! Every single piece of rotating machinery that is not perfectly balanced has "natural" frequencies where vibrations get amplified. So - what can you do about it?

With vibration, a lot of little things add up. (This only applies if nothing is mechanically wrong). I would ask myself about the little things. If it is not speed dependant - then the cause is in the rotating parts of the engine, not the wheels. What changes those forces? Oil, Valve Clearances and spring forces, Timing Chain slack. There are probably others - crankshaft balancing is a biggy.

The easiest to change would be the oil. Go to a synthetic - a lighter weight maybe- and see if it helps or hurts. I doubt it would make too much of a difference. But if it bothers you, then why not try it? The other things I mentioned you can try, but obviously some of them are going to be a lot of work.

You can have someone professionally balance your crankshaft and pistons, and it will probably dramatically improve, but at a higher cost. But, it would also lengthen the life of the engine and improve power slightly!

 

ok i'm new here so forgive me if i step on any toes. as you probably know everything that spins as a "critical rpm" where it shakes like hell, even if its perfectly balanced. bikes have alot of stuff spinning so lots of opportunity for shaking, most of it is tuned so high up into the rpm range that it will never spin fast enough to reach this critical speed. but this can change. i'd say that if your bike shakes at a certain speed/rpm then get a bar snake as suggested already or simply fill the handlebar with lead shot. the second one works really well and its cheap. another thing you can check is wether or not its the speed(which would be your wheels/tires) or if its RPM(this means its engine/driveline). if you can try to hold the same speed in two different gears. if RPM drops/increases and it still shakes then its from the speed. if the RPM drops/increases and the shake is gone then its RPM. wheels tires are easy to balance, engine driveline not so much so.

 

Another area I would be checking out would be the motor mount bushings,when they wear out you get a heck of alot of vibration due to metal to metal contact or slop in them.Just a thought.

 

Blueflame: Between 4700 and 5900 rpm my mirrors vibrate so much that the headlights of cars behind me appear as circles of light. At 6000 rpm the mirrors clear again. Unfortunately this range is where my bike runs in 5th at highway speeds (90 - 120 approx.)

I have read all the posts and have considered many.

My bike has aftermarket (Tommaselli 234 european) bars that were installed when I bought the bike. Further checking has revealed that the original Yamaha handlebar weights are installed in the new bars.

I am considering silicon inthe bars but first want to see what happens without the weights.

 

Well I drove to work this morning without the original weights in the bars. There may have been a bit less vibration at the usual rpm but It certainly has not gone completely away.

Should I try to find a set of stock bars and try those?

 

Question - is your handlebar the only thing that is shaking at that rpm?

If so - then changing the characteristics of the handlebar is the correct answer.

If not - then address the root cause, because there are other things on the bike that don't like vibration. The motor mounts - like kenny said - is an excellent and cheap place to start. Like I said earlier, you could also switch to synthetic oil.

 

Yes I would say that the bar is the only major vibration. Sometimes I can feel them in the footpegs but usually it is the bars and levers that are buzzy.


On the way home today ( without the weights) I found (while stuck in traffic) that the bars vibrate more at low revs without the weights.

i have decided to try the silicone in the bar solution. Should I use the weights and silicone or just the silicone?

 

I would try just the weights first to get an idea as to if they take care of the problem (eazier removal for tuning, Silicone would be a bear to remove if it needs to be later, do this only after you find it works).

 

My original situation was the new bars with the yamaha weights. So the silicone is the next step.

 

Sounds like it may be the steering head bearings causing the vibrations in the handle bars. You might want to try upgrading to tapered steering bearings.

 

kenny just posted my first thought....my left mirror shakes, my right mirror doesnt :| so im gonna be checkin all my bolts in the next couple days... im also gonna be checkin to see if the mirror is just worn out, if it gets real bad it will be like having a bobble-head instead of a mirror, had that prob on my enduro...good luck!

 

Silicon in the bars will do exactly nothing. If you want to have some effect, use lead shot, it will do some damping. I have done both, and speak from experience. Of course, this assumes you will also due everything else to minimize the vibes first, like carb sync, valve adjust, etc. Bar end weights will also have some effect. Buy the heaviest you can get.

 

Silicon is in the bars and there does not seem to be any difference. The bars vibrate at all RPMs but is far worse between 4800 and 6000 rpm. That is the range where the mirrors are useless. Would different bars make a difference?

 

Could it be the bushings for the front fork have worn? I have seen on this board a fair bit of talk about replacing them with bearings, so maybe they are a thing that wears out on these bikes.
Jim

 

Could be as simple as an imbalance on one of the tires. I'd get them checked out as Jason pointed out. There is a harmonic on all tires, the taller the tire, the higher the RPM range where it occurs. My VW had a vibration at 60 MPH that was attributed to this phenomenon.

 

I don't think it would be tire related because it happens at the same rve range regardless of gear. The buzziness is present at various speeds but at the same engine speed.

 

Have you checked the joints on the driveline, could be the shake transfering up to the bars.
just my 2 cents

 

I'd run with Kenny on this one.... I've replaced my motor mount rubbers in the front and rear with great results... mirrors are clear as a bell, and no buzz in the fingers. I got a harmonic thing in the exaust at a certain RPM. i still need to cure.

Jeff

 

My XJ750 bike does have engine vibration at 4500 - 5000 rpms. This is due to worn motor mounts. I have yet to replace them, but it does cause a vibration in the handle bars and foot pegs as well as my left muffler to rattle and annoy me. I either ride below or above the rpms. I did purchase and install a set of Kuryakyn ISO grips and throttle boss which has made all the diffrence in the world on rides. They're prbobably the best investment I've made so far. I haven't added any weights or silicone to the stock bars.

 

My 750 SECA is absolutely terrible with vibrations.
I found this discussion on another forum, perhaps it will be of use...

http://www.xs11.com/forum/showthread.ph ... hreadid=97

Nachoman

 

I have replaced my bars. The new bars are about 2 inches closer to me that the ones the PO put on. This does not eliminate the vibrations but it certainly has reduced their effect on me!!!

I have experimented with positionand found a low but rearward position to work best for me. I am a limited by front brake hose length and am looking for a replacement. I also had to reroute my throttle, clutch and choke cables.

 

Very good thread, but i am suprised more people dont look at the source of the vibration..

the only thing constant @ a said rpm is the drive train.. mainly engine..

wonder how many of the bad vibe storys relate to hard, worn, cheap or bad motor mounts ?

of course the ideas would still be good for road vibration and the vibes you just cant get rid of,

anywho.. my 2 cents seems like people treating the end symptom, not the whole thing.

 

I have been unable to find a reference to rubber motor mounts in the Yamaha parts list.
Do they exist on the SECA?

Nachoman

 

HA!

I found them. They were not listed under the SECA but the Maxim fiche had them. Do you guys think they are the same? I am inclined to believe they are.

I guess I'll have to go check mine now. They probably need replacing.

Nachoman

BTW, the part #'s are as follows. According to the Yamaha site you need two of each.

36Y-15336-00-00
4H7-15316-00-00
3Y6-15326-00-00

 

not listed on the seca fische ?

i have to admit I "assume" there is a damper center on the mount, I havent unmounted mine...

 

Where could a normal person such as myself purchase these motor mount bushings? Do I have to give more money to the stealership or does someone know of a better aftermarket source?

 

Guess I am one of the lucky ones. My 82 xj750j rides smooth as a babys but. Even after replacing the front tire and not getting it balanced, I haven't foud a rpm or speed it vibrates at.

 

Maxim700, I also have an 85 XJ700, I however DONT have that vibration problem.
I'd suggest that you start by process of elimination figuring out what variable(s) cause the vibration.
Is it only when the bike is moving, only at a certain rpm, at a certain speed, when it's warm/cold, etc.
Then I'd start trying to figure what variable I can take away, like speed rpm, temp, etc, to leave the culprit or at least narrow it down.

Is the rpm that vibrates just at 5000 or between 5000 and some other rpm?
Is there a certain speed that it vibrates but it is just coincidence that the rpm happens to be 5000 at that speed?

Let us know what you find out and we can possibly give you a little better tan a "best guess"

Mike

 

JPXJ, a source I've looked at was BikeBandit.com . Rounds out to about $70 but seems fair. Some of the mounts are not available anymore so you may have to fish around. I looked at the mounts between my Max and the Seca and found that I could modify (hacksaw to length) some of the Seca mounts to fit the no-longer-available Max mounts.

 

An awful lot of the dreaded $999 discontinued...

Thanks for the pointer Robert!